[Quoth]

I looked at Solar for the house recently and concluded it was pointless without about 40Ah of 48V batteries per panel. A per panel up converter (it's about 42V max on the panels) for each set of 4 off 12V car batteries (56V fully charged), then diode splitter/combiner for optional mains charging and industrial 48V to 220V AC 2000W inverter/UPS (about 44V to 56V operation) (as used in mobile phone bases, datacentres and telephone exchanges). Cheaper than a grid connected system selling excess to grid. Better value to use it yourself and not sell it. There would never be an overall excess with 6 off standard size panels. It's touch and go without a grant if it would pay back before the panels wear out.

Lead Acid batteries are cheaper than same amount of Lithium and the lead is 100% recycled to new batteries. Lithium only makes sense for portable gear and vehicles. The size and weight is no issue on a UPS or solar system.

I'll wait and see if the grants are improved.